Update app.py via AI Editor

app.py

@@ -360,8 +360,8 @@ def main_callback(upload_filename, upload_contents, delete_file_n, delete_pptx_n
         trigger = ctx.triggered[0]['prop_id'].split('.')[0]
 
     # Always start with current session state
-    upload_file_contents = session_dict.get("uploaded_file")
-    uploaded_filename_val = session_dict.get("uploaded_filename")
+    upload_file_contents = session_dict.get("uploaded_file", None)
+    uploaded_filename_val = session_dict.get("uploaded_filename", None)
     document_text_val = session_dict.get("document_text", "")
     slides_content_val = session_dict.get("slides_markdown", "")
     log_output_children = '\n'.join(session_dict.get("log_messages", [])[:100])
@@ -373,6 +373,22 @@ def main_callback(upload_filename, upload_contents, delete_file_n, delete_pptx_n
     if loading_state is None:
         loading_state = {"show_loading": False}
 
+    # If a new file is uploaded, update session; otherwise, persist current session's file
+    if trigger in ['upload-file', 'upload-file.filename', 'upload-file.contents']:
+        if upload_filename and upload_contents:
+            session_dict["uploaded_filename"] = upload_filename
+            session_dict["uploaded_file"] = upload_contents
+            upload_file_contents = upload_contents
+            uploaded_filename_val = upload_filename
+        else:
+            # Don't clear the session file if not a real upload
+            upload_file_contents = session_dict.get("uploaded_file", None)
+            uploaded_filename_val = session_dict.get("uploaded_filename", None)
+    else:
+        # Don't let interval or other triggers remove file from session
+        upload_file_contents = session_dict.get("uploaded_file", None)
+        uploaded_filename_val = session_dict.get("uploaded_filename", None)
+
     # Delete file logic
     if trigger == 'delete-file-btn':
         session_dict["uploaded_filename"] = None
@@ -387,17 +403,8 @@ def main_callback(upload_filename, upload_contents, delete_file_n, delete_pptx_n
         session_dict["ppt_ready"] = False
         add_log("PowerPoint deleted by user.")
 
-    # File upload/update logic
-    elif trigger in ['upload-file', 'upload-file.filename', 'upload-file.contents']:
-        # Only update if a new file has been uploaded
-        if upload_filename and upload_contents:
-            session_dict["uploaded_filename"] = upload_filename
-            session_dict["uploaded_file"] = upload_contents
-            upload_file_contents = upload_contents
-            uploaded_filename_val = upload_filename
-
-    # Text content update
-    elif trigger in ['document-text', 'slides-content']:
+    # Text content update (manual text or slides markdown edits)
+    if trigger in ['document-text', 'slides-content']:
         session_dict["document_text"] = doc_text_input
         session_dict["slides_markdown"] = slides_input
         document_text_val = doc_text_input
@@ -410,7 +417,6 @@ def main_callback(upload_filename, upload_contents, delete_file_n, delete_pptx_n
         loading_children = html.Div("Generating slides, please wait...", className="text-center")
         to_send = ""
         file_text = ""
-        # Always use current session state for file
         if session_dict.get("uploaded_file") and session_dict.get("uploaded_filename"):
             try:
                 file_text = process_uploaded_file(session_dict["uploaded_filename"], session_dict["uploaded_file"])
@@ -418,11 +424,13 @@ def main_callback(upload_filename, upload_contents, delete_file_n, delete_pptx_n
                 add_log(f"File error: {str(e)}")
                 session_dict["slides_markdown"] = f"File error: {str(e)}"
                 slides_content_val = f"File error: {str(e)}"
+                loading_children = ""
+                loading_state = {"show_loading": False}
                 return (get_uploaded_file_area(session_dict),
                         get_pptx_download_area(session_dict),
                         upload_file_contents, document_text_val, slides_content_val,
                         '\n'.join(session_dict["log_messages"][:100]), download_data,
-                        session_init_data, "", {"show_loading": False})
+                        session_init_data, loading_children, loading_state)
         if doc_text_input:
             session_dict["document_text"] = doc_text_input
         if file_text and doc_text_input:
@@ -431,11 +439,13 @@ def main_callback(upload_filename, upload_contents, delete_file_n, delete_pptx_n
             to_send = file_text or doc_text_input
         if not to_send.strip():
             slides_content_val = "Please upload a file or enter text."
+            loading_children = ""
+            loading_state = {"show_loading": False}
             return (get_uploaded_file_area(session_dict),
                     get_pptx_download_area(session_dict),
                     upload_file_contents, document_text_val, slides_content_val,
                     '\n'.join(session_dict["log_messages"][:100]), download_data,
-                    session_init_data, "", {"show_loading": False})
+                    session_init_data, loading_children, loading_state)
         try:
             add_log("Starting slide generation...")
             slides_markdown = process_document(to_send)
@@ -480,13 +490,10 @@ def main_callback(upload_filename, upload_contents, delete_file_n, delete_pptx_n
             loading_children = ""
             loading_state = {"show_loading": False}
 
-    # Interval/log update
+    # Only update the log output on interval, never touch file upload or loading on interval
     elif trigger == 'interval-component':
         log_output_children = '\n'.join(session_dict.get("log_messages", [])[:100])
-
-    if not show_loading and isinstance(loading_state, dict):
-        if not loading_state.get("show_loading", False):
-            loading_children = ""
+        # Do not touch loading_children or loading_state
 
     # Always persist session state for these keys
     session_dict["uploaded_file"] = upload_file_contents
@@ -494,6 +501,11 @@ def main_callback(upload_filename, upload_contents, delete_file_n, delete_pptx_n
     session_dict["document_text"] = document_text_val
     session_dict["slides_markdown"] = slides_content_val
 
+    # Only show dcc.Loading spinner when generating slides or pptx, not on interval or other triggers
+    if not show_loading and isinstance(loading_state, dict):
+        if not loading_state.get("show_loading", False):
+            loading_children = ""
+
     return (get_uploaded_file_area(session_dict),
             get_pptx_download_area(session_dict),
             upload_file_contents, document_text_val, slides_content_val,